Chiral Symmetry Breaking and Intersecting D-brane Systems
نویسنده
چکیده
The general theme of these lectures is the use of the tools of string theory, in particular D-branes [1] and holography [2], to study chiral symmetry breaking in the strong interactions. Recall that QCD with Nf falvors of massless quarks with left and right-handed components qL, qR has a symmetry group U(Nf )L × U(Nf)R which acts as independent unitary rotations of qL, qR. We know from the identification of pions as NambuGoldstone bosons that this symmetry is spontaneously broken:
منابع مشابه
Intersecting Branes Flip SU ( 5 )
Within a toroidal orbifold framework, we exhibit intersecting brane-world constructions of flipped SU(5) × U(1) GUT models with various numbers of generations, other chiral matter representations and Higgs representations. We exhibit orientifold constructions with integer winding numbers that yield 8 or more conventional SU(5) generations, and orbifold constructions with fractional winding numb...
متن کاملIntersecting branes and Nambu−Jona-Lasinio model
We discuss chiral symmetry breaking in the intersecting brane model of Sakai and Sugimoto at weak coupling for a generic value of separation L between the flavour D8 and anti-D8-branes. For any finite value of the radius R of the circle around which the colour D4-branes wrap, a non-local Nambu−Jona-Lasinio (NJL) type short-range interaction couples the flavour branes and anti-branes. We argue t...
متن کاملar X iv : h ep - t h / 02 06 08 7 v 1 1 1 Ju n 20 02 ACT - 05
Within a toroidal orbifold framework, we exhibit intersecting brane-world constructions of flipped SU(5) × U(1) GUT models with various numbers of generations, other chiral matter representations and Higgs representations. We exhibit orientifold constructions with integer winding numbers that yield 8 or more conventional SU(5) generations, and orbifold constructions with fractional winding numb...
متن کاملTIFR Annual Report 2008-09 THEORETICAL PHYSICS String Theory and Mathematical Physics
Chiral symmetry breaking in a non-local Nambu-Jona-Lasinio like 4-fermi model, derived from the intersecting brane model of Sakai and Sugimoto in the weak coupling limit, was found to occur only above a critical value of the coupling. Numerical investigations showed, contrary to what had been suggested in the literature, that this feature persists even when the radius of the circle on which the...
متن کاملGauge Unification via Stable Brane Recombination
We study the transition between parallel and intersecting branes on a torus. Spontaneous symmetry breaking of nonabelian gauge symmetry is understood as brane separation, and a more general intermediate deformation is discussed. We argue that there exists supersymmetry preserving transition and we can always have parallel branes as a final state. The transition is interpreted due to dynamics of...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2007